This invention relates to novel polymers and more particularly to high performance polymers provided by a cross-reaction involving an organic oligomer, particularly oxirane oligomers.
The formation of tri and tetra functional oxirane polymers such as polyglycidyl ether of phenolformaldahyde novolac, glycidoxy tetraphenylethane, and tris (hydroxyphenyl) methane triglycidal ether are well known but have processing problems in that when these epoxies are homopolymerized, they form brittle structures. Since homopolymerization gives the best temperature and chemical resistance from these tris and tetra epoxies, brittleness becomes its biggest detractor. A further drawback of these epoxies is that they are high melting point solids.
The advantage of the present invention is that high molecular weight polymers can be made from lower molecular weight oxirane oligomers giving the new polymers high aromatic groups for chemical and temperature resistance and high ether groups for elongation and toughness.
Previously, work has been conducted with respect to increasing the molecular weight of oxirane polymers by their catalyzed reaction with dihydric phenols. Epoxy resins cross-linked with dihydric phenol, such as resorcinol, hydroquinone, bisphenol A, etc. are well known. For example, U.S. Pat. No. 3,643,323, herein incorporated by reference, discloses an epoxy resin prepared from a 1, 2 epoxy and a dihydric phenol in the presence of one or more advancement catalysts.
However, increasing the molecular weight of oxirane oligomers with tris-phenyls, such as tris (P hydroxy-phenyl) ethane or tris (4-hydroxyphenyl) 1,3,5-trisispropylbenzene has not been performed. The particularly molecular structures of these presently preferred phenyls include the following. Tris (P-Hydroxy-Phenyl) ethane, a solid at room temperature having the molecular structure: ##STR1##
Molecular weight: 306
Melting point: 247.2.degree. C.
Tris (4-Hydroxy-Phenyl) 1, 3, 5-trisispropylbenzene, a solid at room temperature having the molecular structure: ##STR2##
Molecular Weight: 480
Melting point: 189.degree. C.